I agree that alcoholism and depression are diseases that many Americans suffer from and need to be addressed with more than criticism.
The part I fail to understand about Anthony's song is when he criticizes individuals who suffer from poor nutrition or food addiction as if it is an affront to him personally. He seems to be saying that these people are on welfare, and he resents them for eating too much. His words reminded me of the tired Ronald Reagan trope about the 'welfare queen' and how she is living the high life at the expense of working Americans-- 5'3" and 300 pounds.
I'd like to see Anthony reach beyond this simplistic explanation and address issues such as the corporate welfare that permeates our country and creates such low wages, despite enormous profits, and forces working Americans to seek welfare because they can't afford to survive despite working full time.
Personally, I found education to be the great equalizer as far as income and opportunity, and it has improved my life, and so many other's lives, in numerous ways. Labor jobs, without a high school diploma, tend to be low paying and soul sucking. You exist at the bottom of the food chain, and the only question is what are you going to do about it.